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hi, any ideas how to convert Rcd and Dst seismic data into SEGY?

any ideas how to convert Rcd and Dst seismic data into SEGY?
Morad Muafa's user avatar
0 votes
0 answers
43 views

Zoeppritz equations

I have a question regarding zoeppritz equations. The equations from Telford are as follwoing: When trying to put in a matrix form, by converting amplitudes to reflection and transmission coefficients,...
user31690's user avatar
1 vote
0 answers
42 views

What happens to seismic waves reflected back to the surface?

What would be the behavior of seismic waves when it hit the geological media? The waves coming from a source hits different boundaries with different energies, the wave will be reduced in energy by ...
Ahmed Zeglam's user avatar
1 vote
0 answers
158 views

SEG-2 vs SEG-Y file formats

I have limited experience with the different SEG file formats and I was hoping if someone could shed some light on the current preffered file formats used in software applications and for sharing ...
MJ_Wales's user avatar
6 votes
2 answers
125 views

How to produce random numbers from seismic data?

I have read that the University of Chile uses seismic data to produce random numbers. (https://random.uchile.cl/randomness-beacon). Does seismic data real have randomness and if it so, which ...
ofenerci's user avatar
  • 163
2 votes
1 answer
79 views

How to quantitively compare two seismic waveform data?

Our group has built an Arduino-based device with an MPU6050 to act as our seismometer for our project, with the data being displayed on Amaseis. Our proctor demands that we quantitively assess its &...
antuK3n's user avatar
  • 21
1 vote
1 answer
35 views

Estimation of velocity of the wave from seismic trace

How can seismologists estimate velocity (on the different layers) of the wave propogated through the earth , only from given seismic trace(s) ?
Fearless_Wolf's user avatar
2 votes
1 answer
59 views

If deterministic wavelet is better for well ties , why do people use statistical wavelet too for wellties?

Synthetic trace generated with deterministic wavelet gives a higher correlation with real seismics. Though it's more accurate for seismic well ties than statistical wavelet, but there is always an ...
Fearless_Wolf's user avatar
5 votes
1 answer
116 views

What is the purpose of wavelet extraction from the seismic trace?

I would love to know what exactly we can do with the extracted wavelet. What kind of information extracted wavelet can contain?
Fearless_Wolf's user avatar
3 votes
1 answer
108 views

Predicting rock type from seismic processing

In reflection seismology, we create a source with an airgun and then use receivers to register acoustic waves (an approximation) at the surface. From these measurements, we can predict a velocity ...
TylerMasthay's user avatar
5 votes
1 answer
167 views

Is there a seismic discontinuity between the lithosphere and asthenosphere?

I've been learning about seismic discontinuities, mainly the 5 defined ones - Conorod discontinuity, Mohorovicic discontinuity, Repetti discontinuity, Gutenberg discontinuity, and Lehmann ...
Sasikuttan's user avatar
4 votes
0 answers
35 views

Seismicity associated with post glacial rebound

Allied to the question: Why is relative sea-level falling in Hudson Bay?, where the surviving answers mention post glacial rebound. Is seismicity associated with post glacial rebound and if so what is ...
Fred's user avatar
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Are there specific layers in the subsurface that come before gas or oil?

Currently, I've started working on a geophysics project. More specifically, I'm trying to find gas and oil reservoirs in SEGY files using deep learning. I've been reading about seismic reflection ...
hrmello's user avatar
  • 19
1 vote
0 answers
60 views

What are the boundary conditions for Navier's Equations of motion in seismic?

Navier's equations of motion in seismic have 3 solutions, according to how it is resolved (boundary conditions): for Vp (compression waves) for Vs (shear waves) for Vr (Rayleigh waves) I know the ...
JCV's user avatar
  • 111
1 vote
0 answers
34 views

Preconditions for stacking

Some of the requisite for stacking is that the noise and amplitudes need to be uncorrelated. Can someone explain to me why? Also is there a drawback for stacking?
ggraann's user avatar
  • 21
1 vote
0 answers
91 views

Quality control in Seismic Acquisition - shot offset shift

I have a problem with seismic data where the minimum offset of the shot is not centered at the nearest receiver, this shift can be for 3 traces 2 or one and maybe more in the two sides !! So is there ...
Djabri Josef's user avatar
1 vote
0 answers
23 views

Conversion of SEG-Y relative to MSL

I am working on the conversion of CSF file from SonarWiz into SEG-Y data. However, it comes back always related to the Sensor depth/altitude and never to the MSL. I have tried changing the bytes from ...
Patricia Esteves's user avatar
2 votes
1 answer
78 views

Recent high seismic activity in Europe

It seems that Europe and the Mediterranean Sea have had high seismic activity in last six months. Major events which I remember are: 2020 Aegean Sea earthquake, magnitude of 7.0 Mww 29 December 2020:...
user22053's user avatar
1 vote
1 answer
142 views

What would be the phase shift and polarity of a seismic wave upon reflection

What would be the phase shift and polarity of a seismic wave a) when it hit the free surface b)when the free surface reflection goes down and hit a reflector and returned to the receiver placed on the ...
simond's user avatar
  • 111
4 votes
0 answers
226 views

Beam forming FK analysis of a seismic wave

So after reading alot of literature on source localization, I found out that FK analysis is one of the most widely used methods to determine source location without explicitly calculating the ...
Sanika Khadkikar's user avatar
1 vote
0 answers
60 views

How does uplift lead to onlapping?

I read in a paper that: Interpretation of 2-D seismic lines shows the lower to middle Patchawarra Formation onlapping onto paleostructural highs at approximately 270 Ma and again at 273 Ma, ...
user20637's user avatar
1 vote
1 answer
999 views

How do we know the speed of S-waves (shear waves) in the Earth's inner core? Has this been measured?

Wikipedia's Seismic wave includes the plot below of the speed of S and P waves as a function of depth in the Earth. In the region of the outer core the speed of S-waves or shear waves is shown to be ...
uhoh's user avatar
  • 7,122
1 vote
1 answer
88 views

Q factor estimation from VSP

in seismic data processing there is a step of calculating the absorption represented By Q value which is Q factor , how we can estimate it from VSP ! thank you.
Djabri Josef's user avatar
2 votes
3 answers
273 views

stretch phenomena after NMO application on seismic data

after the NMO application we have stretch for far offset , i read a lot of articles but i can't have a complete idea how this phenomena is really created ! any one have a rich explanation ?
Djabri Josef's user avatar
1 vote
1 answer
108 views

Where can I find broadband seismic reflection data?

or what type of companies should I contact to ask for the data? This data would be produced from Seismic Vibroseis survey trucks which are mostly used to locate oil and gas. I doubt most oil and gas ...
Mark Fisher's user avatar
3 votes
1 answer
2k views

Why do P waves have a higher velocity in the lower mantle than in the core even though the core has a much higher density?

I've just started teaching 9th grade Earth science and my students and I have noticed something about P and S wave depth vs velocity graphs. In the typical graph, eg: https://www.researchgate.net/...
Greg Walsh's user avatar
1 vote
1 answer
172 views

Hydrophone/geophone sensor sensitivity - noise versus signal

Today, a student asked this question, and I was unable to answer it in a way that was understandable and accurate - even for myself. For seismic data acquisition projects, how are sensors able to '...
nate's user avatar
  • 796
2 votes
1 answer
153 views

Using an accelerometer as a geophone to conduct a seismic survey

I am doing a capstone project for a sensor systems course and I would like to write a python program to acquire, process and present seismic data like that of seismic surveys. Is it possible using ...
Hydrogen 7's user avatar
1 vote
0 answers
162 views

Finding out actual dip and dip direction of refractor

We have two traveltive curves for first arrivals (direct and refracted) from a dipping refractor in the forward and reverse directions along a profile line. my question is: Is there a logical way (non-...
Elisavet Kollia's user avatar
3 votes
2 answers
155 views

Is it reasonable to approximate the swinging building (base of the building) during an earthquake to a simple harmonic motion?

I am thinking of making a model of swinging building during earthquake and study the methods to minimize the swinging. So does it even makes sense to approximate the swinging buildings (the base of ...
shinigami's user avatar
4 votes
0 answers
49 views

Seismic velocity inversion & analysis

I attended at talk recently at the TGS office in Houston, TX, by Marianna Raunch. During this talk, a statement was made that for "very large" velocity inversions, semblance (or other similar ...
nate's user avatar
  • 796
3 votes
1 answer
112 views

Wave train 200 m/s meaning

I ran a 60 m line intended for surficial seismic refraction. Energization with hammer. 12 (10 hz vertical 5 m spaced) geophones and 5 shots (15 m spaced). Record length 0.5 s. Thanks to a borehole ...
Carlos Javier's user avatar
4 votes
1 answer
215 views

wavelength of seismic wave with a gaussian source

I want to know how to get the wavelength/frequency of a seismic wave, if I only have a Gaussian source and the velocity (c = 4000m/s) of a medium given. e.g. for a Ricker wavelet it would be easy to ...
guest101's user avatar
2 votes
1 answer
50 views

Seismic amplitude distribution

Recorded (or raw) and processed pre/post-stack seismic data (relative amplitudes) usually display a standard normal distribution, albeit with a very small amount of skewness. What would be possible ...
nate's user avatar
  • 796
1 vote
1 answer
39 views

Seismic wavefield theory: velocity anisotropy

Does the reciprocity principle hold true in an anisotropic subsurface environment?
nate's user avatar
  • 796
2 votes
1 answer
102 views

What is the vertical axis of this waveform shown in this tweeted IRIS GIF?

This IRIS tweet shows a video of siesmic waves from the recent M6.4 Earthquake in California rolling across the US. I've made a small GIF to give the idea but the "GIF" in the tweet shows the whole ...
uhoh's user avatar
  • 7,122
1 vote
1 answer
236 views

How to read Seismic Survey?

Recently I am tasked to create a POC on detection of patterns using a neural . But I am from a computer science background so I know about neural networks but I don't have any knowledge about geology ...
Himanshu Bansal's user avatar
1 vote
1 answer
228 views

wave speed is smaller than both horizontal wave speed and vertical wave speed?

I am new to GIS and just get the idea of slowness. I can understand why people need the slowness in GIS rather than just the reciprocal of velocity. However, I feel the definition of slowness is weird ...
Silentmovie's user avatar
1 vote
1 answer
155 views

reverse time migration for wave equation PDE using SBP-SAT

I'm stuck implementing a reverse time migration technique, the PDE(partial differential equation) being implemented is an acoustic wave equation, The numerical method being used is a FD(finite ...
Karim Morad's user avatar
3 votes
2 answers
1k views

Travel Times for Seismic Wave Types - Why reflected t-x plot curves

I do not understand how the reflected wave in a seismic survey has a steepening slope (slows down) Please bear with me as I lay out my thoughts because I feel like I can grasp all of this except this ...
MattGeo's user avatar
  • 303
1 vote
1 answer
107 views

Near-Surface Investigations: FWI vs. MASW

MASW is a common processing method for civil/geotechnical and even for oil/gas exploration (usually weathering static corrections) applications. In my experience, it seems to work well for most ...
nate's user avatar
  • 796
4 votes
0 answers
79 views

Seismic data acquisition: reliability of high-bandwidth data

In my research, finding and understanding info relating to the lower end of (conventional) surface seismic data acquisition (i.e. 15 - 1 Hz) is relatively simple. However, when I look at specs for a ...
nate's user avatar
  • 796
1 vote
1 answer
92 views

Love-Wave Propagation

Love-waves cannot exist in a half-space. Layering must be present and there also must be accompanied impedance contrasts associated with the layering. Because layering naturally induces seismic ...
nate's user avatar
  • 796
3 votes
0 answers
67 views

Difference between landslide waves and earth quake waves

I am new to this field, recently started working on landslide monitoring mainly in signal processing part. I have the following questions? 1.Will each land slide and every vibration have p wave, s ...
Abhishek's user avatar
1 vote
1 answer
462 views

Quality control in Seismic Acquisition - How much data is required?

When it comes to land or marine acquisition (oil exploration, for instance), I can see from literature that quality control (QC) is performed during the survey to ensure that the seismic traces ...
V-Red's user avatar
  • 141
2 votes
2 answers
2k views

converting segd data to SU format using seismic unix

I tried to convert segd format to su format using seismic unix by below command: segdread tape=1.segd > 1.su but I have an error: ...
Nora11's user avatar
  • 21
2 votes
1 answer
94 views

Basic petrophysics

The following question was inspired by Effective pressure or what is the effect of presssure?, which may be accessed here: https://inside.mines.edu/UserFiles/File/CRA/2005/...
nate's user avatar
  • 796
2 votes
1 answer
266 views

DC component in Hilbert transform concept for seismic data

In The Leading Edge tutorial article Phase and the Hilbert transform (Purves 2014), there is the following line: So we apply a Hilbert transform by multiplying all negative frequencies by i and all ...
nate's user avatar
  • 796
5 votes
0 answers
58 views

How do I generate a Moho depth model from seismic refraction data?

There are several permanent seismograph stations in Eastern Canada that have been recording arrival times for over 25 years. Using refracted Pn arrival times from natural earthquakes I would like to ...
Alex Koldewey's user avatar
1 vote
1 answer
148 views

Spectral Whitening, Seismic Interferometry

What is the role of spectral whitening in the processing step done before cross-correlations in seismic interferometry?
nooob's user avatar
  • 11